Optical fiber cables have been utilized in a wide variety of different application, such as premise, underground, and aerial applications. In aerial applications, a cable is typically suspended between two poles or other points, thereby subjecting the cable to tensile stresses and environmental stresses (e.g., temperature stresses, wind, snow, ice, etc.). These stresses can lead to increased optical fiber attenuation and negatively impact cable performance. In order to address aerial applications, certain cables include messenger or suspension wires that help to support the cable's load; however, these wires increase installation cost and may attract lightning. To avoid messenger wires, all-dielectric self-supporting (“ADSS”) cables have been developed in which optical fibers are positioned within loose buffer tubes that are stranded around a central strength member. Aramid yarns are then wrapped around the buffer tubes in order to support the weight of the cable over suspended areas. The materials in the cables are exclusively dielectric in order to avoid lighting strikes and to allow the cables to be placed in power regions, such as power regions of a pole from which the cables are suspended.
The stranding of aramid yarns around the optical fiber buffer tubes increases the weight, cost, and overall diameter of conventional ADSS cables. As a result of wrapping the aramid yarns around the buffer tubes, a greater amount of aramid material must necessarily be used. The amount of needed material increases as the number and/or size of the buffer tubes increases. Accordingly, there is an opportunity for improved ADSS cables that incorporate flexible strength members, such as aramid yarns, into a central strength member. In particular, there is an opportunity for improved ADSS cables in which a central strength member includes both a relatively rigid layer and a relatively flexible layer.